For the past 2-3 months, I've been thinking through the details of implementing the last great web app, the shareable calendar. I believe it is time to bring the calendar into the world of Ajax and RSS. I was excited a few weeks ago when Novell announced that it was open sourcing its Hula Project. Hula provides a great platform to build the next generation calendar.
I want to see a calendar that has the simplicity and responsiveness of Tada List. I want to be able to see the details of a day by simply hovering my mouse over a cell in a monthly view. I want to be able to start entering an event with just one click, without having the page reload. I believe, with proper design, a calendar can be functional, and not be complicated and cluttered like Yahoo!'s Calendar. Yahoo has just too many boxes, lines, and ads that distract. It seems like the web is moving away from portals that do everything, to specialized sites that do one thing really well. I don't need a todo list with my calendar, I already have that covered, I just want a calendar.
If a popular calendar site comes out and gets widely adopted, it may even sway people away from Outlook/Exchange or force Microsoft to implemented a non-proprietary calendar standard such as iCalendar. This will help immensely in alleviating the synchronization issue.
How do you make money with it? I'm sure the big guys like Google will obviously want to make money doing something like this. One thing I can think of is to have sponsored events during the free time on your calendar. Google can index the past history of your calendar and suggest things for you to do in your spare time based on this history. For example, lets say you had an event for a rock concert a few weeks ago. Google can now add a sponsored event this coming weekend for a another rock concert, with a link to Ticketmaster. Obviously this event will be transparent and will not trigger any reminders. This model can be made to operate just like AdWords. However, if it is too intrusive, they can simply list the ads on the side like they do now. I believe its worth the experiment.
It looks like I'm not the only one who has been thinking about this.